1. Field
The present disclosure relates generally to composite structures and, in particular, to reworking composite structures. Still more particularly, the present disclosure relates to a method and apparatus for reworking inconsistent areas of composite structures using a patch with a tapered adhesive design.
2. Background
Composite structures sometimes have localized areas containing one or more inconsistencies that may require rework in order to bring the structure within design tolerances. These inconsistencies may include, for example, without limitation, a crack, delamination, and other types of inconsistencies formed during the lifecycle of a composite structure.
Oftentimes, an inconsistent area of a composite structure is reworked using a patch. This patch may comprise composite materials, metals, or a combination thereof. Different types of techniques may be used to rework the composite structure using the patch.
For instance, a patch may be placed over the inconsistent area and secured to the parent structure using mechanical fasteners. The condition of the patch may be monitored over time by visually inspecting the fasteners.
In other cases, a rework patch may be secured to a parent structure using a bonded joint. This technique may also require the use of mechanical fasteners that provide secondary load paths forming an arrestment mechanism to limit the growth of an inconsistency.
These types of patching techniques, however, may not perform as desired when the composite structure is an aircraft structure. For example, the use of fasteners may increase aircraft weight, drag on the aircraft, or both more than desired. As another example, a bonded patch may not reduce the spread of the inconsistency in a desired manner. Therefore, it would be desirable to have a method and apparatus that take into account at least some of the issues discussed above, as well as other possible issues.